Twin circular sawing machine



(No Model.) a Sheets-Sheet 1.

M. GARLAND. k TWIN CIRCULAR SAWING MACHINE. No. 518,031

E NATIONAL LITMDGRAPNINO COMPANY wAeumavon. D. c.

(No Model.)

M. GARLAND. TWIN CIRCULAR SAWING MACHINE.

No. 518,031. Patented Apr. 10, 1894. A

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M. GARLAND. TWIN CIRCULAR SAWING MACHINE.

No. 518,031. Patented Apr 10, 1894.

UNITE STATES" PATENT OFFICE.

MICHAEL GARLAND, OF BAY CITY, MICHIGAN.

TWIN CIRCULAR SAWING MACHINE.

SPECIFICATION forming part of Letters Patent No. 518,031, dated April 10, 1894 Application filed November 27, 1893. Serial No. 492,061- (No model.) I

To all whom it may concern.-

Be it known that I, MICHAEL GARLAND, of Bay City, in the county of Bay and State of Michigan, have invented a certain new and useful Improved Twin Circular Sawing Machine; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming part of this specification.

Previous to my invention, what are known as twin circular sawing machines have been made, in which two saws arranged in parallel vertical-planes have been used, to first simultaneously slab offopposite sides of the log, fed through the machine, and to subsequently saw off two boards at once, by an adjustment of the saws closer together.

I propose to provide for use a twin circular machine in which a series of twin saws operate, at one run of the carriage, to simultaneously slab ofi both sides of the log, and also saw off two boards; thus greatly increasing the out put of the mill in a given time, or with a given number of runs of the log-carrlage.

My invention also has, for a further object, to provide for use a machine which, while it will serve the purposes just above mentioned, will also work very efficiently, and so that boards of various thicknesses can be cut at the same time; and to these-main ends and objects, my invention consists in the novel combinations of devices which will be hereinafter fully described, and which will be found most particularly pointed out in the claims of this specification.

To enable those skilled in the art to which my invention relates, to make and use machines containing, either wholly, or partially, my improvements, I will now proceed to more fully describe thelatter, referring by letters to the accompanying drawings which form part of this specification, and in which I have shown a machine embracing the several features, or, parts, of my invention, and carried into effect in that form in which I have so far successfully practiced the same.

In the drawings, Figure 1 is a perspective View of myimproved machine. Fig. 2 is a plan, or top, view of the same. Fig. 3, is a detail vertical section, at line an, 0c, of Fig. 2.

In the several figures the same part will be found always designated by the same letter of reference.

A is the main frame work of the machine, in which are mounted all the working parts, except, of course, the log-carriage, and its op-' erative mechanism which are arranged, about as usual, with the track, or chain race G 10- 6o cated as seen; the driving mechanism of the endless carrier chain G being beneath the floor on which the track G and saw frame A are supported, and, hence, not seen in the drawings.

On the main frame A are mounted, in suitable journal boxes, two mandrels, or saw shafts, M and M on which are mounted, respectively, the two sets of saws (or the twin circulars) B, B, and D, D, and each of said shafts is provided, as shown, with a drive-pulley, E and E.

L is a log, shown as properly placed on the track G, on which it is carried along by the carrier-chain G one of the dogging teeth, or devices, G? of which (thatengage with the lower surface of the log) is seen at Fig. 1; all in about the usual manner of a twin circular; while I is the binding roll, made and mounted so as to operate in the well known manner.

Running transversely of the main frame A, and securely fastened to the forward portion thereof, are two round bars, a, a, on which are mounted two sliding blocks B B each of which carries a pair of inwardly projecting guide pins b between which pins runs one of the saws B, and by which said saw is laterally held and guided during its rotation.

On the forward part of the frame-work A is also mounted, in suitable journal boxes, a rotary screw shaft e, the thread of which engages with female threads in the blocks B B (through both of which said screw shaft passes), and which is provided, at one end, as 9 5 shown, with a bevel gear 0 that meshes with a bevel pinion on the inner end of a short crank shaft g, that is arranged in a block, or stand, f, secured to the cross-bars a, a, of the machine, andthat is provided with a handle roe 0 all as clearly shown. By turning this handle around in one, or the other, direction, the screw shaft e is revolved, and by its rotation, the'blocks B B are caused to slide (on'the bars a, a), and are moved, with a uniform motion, either nearer together, or farther apart, according to the direction in which the shaft e is revolved. This movement of the gulde-blocks B B operates, through the medium of the two pairs of guide pins b to adust the forward saws B, B,and set them, either nearer together, or farther apart.

In practice, I have used a screw shaft e having four threads to the inch, so that four turns, or revolutions, of the crank handle 0 effects a movement, or lateral adjustment, of each saw B, one inch.

In order that the attendant may readily set the saws with exactitude, I arrange a crossbar at d that is provided with an index 01 the points, or teeth, of which are say, one

inch apart, and which project toward the teeth of one of the saws, and so as to come tolerably close thereto when the saw may be set in a vertical plane coincident with that in which any one of the index points lies. As the two saws are forced to move always to the same extent, though in opposite directions,it follows that when one saw may be moved a glven distance, by the index, the other one will be adjusted to precisely the same extent, I

and, hence, when one of the saws B is set to cut, or saw 0%, an inch board from that side of the log on which said saw operates, the other saw will be set to cut an inch board from the other side of the log. Each pair of guideplns is composed of two set screws mounted in a pair of arms, so that by the turning of these screw pins each saw may be set, to start with, in exactly the properposition, and each will be held and guided laterally at a point a short distanceinside of the toothed pe- I riphery of the saw, and a little way above the upper edge, or line, of the kerf cut by the saw.

On the bars a, a, is mounted,-as shown, another stand, or block, it, which is provided with a rotatory arbor, on the inner end of which is made fast a chain wheel '5, and the outer end of which is provided with a handwheel F. And by means of said hand-wheel to rotate the sprocket-wheel 't', the attendant is enabled, through themedium of the endless chain F that passes down through the floor, and is handed on to awheel not shown, to control, or regulate the mechanism by which the log is fed through the machine.

A visual inspection of Fig. 1 will make clear the fact that when the log L is first fed through the machine, the twin saws B, B, (being properly set) will out two slabs from the opposite sides of the log, and it will be understood that when these saws shall have been properly ad- I justed they will, at each successive run of the logLthrough the machine, cut ofi boards. But, as already explained, another pair, or set, of saws D,D, are arrangedin rear of those marked B, B, and this second set of saws, it will be understood, is adjusted, or set, always to cut inside of the lines, or planes,in which the forward set cuts; so that, as the log L runs through the first time, the twin saws B, B,

off, and so on, until the log shall have been sawed up into boards,leaving,however,atwo inch board at the middle of the log.

The rear set of saws D, D, are similar to those marked B, B, and the mounting, adjusting, mechanism, 850., are all the same. As, however, they are at the rear of the machine, a long shaft, or arbor e that carries at its inner end the bevel pinion that engages with the gear of the rear screw shaft, extends forward from the stand f and, having its forward portion journaled in a similar stand, or block, f is provided with a hand crank d by means of which the attendant can effectuate the adjustment, or setting of the rear saws, as conveniently as that of the front pair, which he controls by means of the crank handle C as heretofore explained.

By means of the two sets, or pairs, of saws B, B, and D, D, arranged as herein shown and described; and an adjusting mechanism combined with each set, as described, the machine is rendered capable of cutting, from the opposite sides of the log, more boards, at one run of the log-carrier, than could be cut by a single twin circular, and, at the same time,

may be run so as to cut a thick and a thin board at each side of the log.

By having the saws clear the log-carrying chain, as shown, I am enabled, with mymachine, to saw up closer to the center of the log than was possible in machines made, as heretofore, with either the log-carriage, or the carrier-chain (as the case might be) arranged at such height, as to pass between the lower portions of the two saws. In such case as the carrier chain alone is about five and a half inches wide, the saws could never out closer together than about six inches. In my machine the saws cut kerfs above (though extending down close to) the upper part of the carrier-chain, and, hence, can out very close up to the center of the log.

The combination with each saw of the guidepins arranged to hold the saw at a point just in rear of where it is cutting, I deem important, as thereby the machine is rendered efficient and perfect in its operation, so far as the action of the saws is concerned.

Of course, the log may be fed, or carried, by a carriage, driven by a steam feed cylinder in the well known manner, in lieu of by the chain shown working in a race, or log chute, without departing from the principle of my improved machine, and other modifications, as well as variations of details may be made without changing its novel mode of operation. I do not, therefore, wish to be re-. stricted to the precise forms shown, so long as the machine contains what I have pointed out as its essential novel characteristics, chief among which are, the series of pairs of (or twin) saws, arranged to cut one set in rear of another; the arrangement of the saw mandrels above the log, so that the log carrierchain, or device, need not pass between any two saws; the guidance laterally of the saws as they enter, or cut, into the log; and having each pair, or set, of saws adjustable, by means of a separate saw setting mechanism.

Having now so fully explained my novel construction of twin circular sawing machines that those skilled in the art can make and use machines containing, either wholly or partially, the separable features of my inven:

tion, what I claim as new, and desire tosecure by Letters Patent, is-

1. The combination of the two pairs of circular saws, arranged to cut, one pair in advance of the other, and the saws of each pair on opposite sides of the log; and separate, or independent, setting-mechanisms; each operating to set the saws of one pair; all substantially in the manner and for thepurposes hereinbefore set forth.

2. In a twin-circular sawing machine of the type herein shown and described, the combination, with a suitable frame -work; and shafts on which to mount them, of a series of sets of circular saws operating simultaneously upon the log to be cut up from the time its leading end comes into contact with the second set of saws until its tail end passes beyond the action of thefirst set, and arranged so that the saws of each set out simultaneously at opposite sides of the log, and in vertical planes; and so that the saws of the several sets out one setin advance of another but in differentplanes; all substantially in the manner and for the purposes hereinbefore set forth.

In witness whereof I have hereunto setmy hand this 15th day of August, 1893.

MICHAEL GARLAND. In presence of- GEO. WATKINS,

EM. TOMPKINS. 

